In a small saucepan, melt butter; stir in the seasonings and garlic. Place chicken breast side up on a rack in a shallow roasting pan; tie drumsticks together with kitchen string. Spoon half of the butter mixture over chicken. Place the potatoes, carrots and onions around chicken. Drizzle remaining butter mixture over vegetables. , Bake at 350° for 1-1/2 hours. Baste with cooking juices; bake 30-60 minutes longer, basting occasionally, until a thermometer inserted in thickest part of thigh reads 170°-175°. (Cover loosely with foil if chicken browns too quickly.), Let stand 10-15 minutes, tented with foil if necessary, before carving. Serve with vegetables.